Reviewed by USGSArgentina19y ago
M4.4 earthquake 15 km NNW of San Antonio de los Cobres, Argentina
Thursday, April 26, 2007, 05:26:54 UTC · 24.097°S, 66.400°W
A magnitude 4.4 earthquake struck 15 km NNW of San Antonio de los Cobres, Argentina on Thursday, April 26, 2007, 05:26:54 UTC, at a depth of 77.2 km (intermediate).
- Magnitude
- 4.4
- Light · mb
- Depth
- 77 km
- Intermediate
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- —
- No ShakeMap
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquakeDashed circle: 50 km aftershock search area
In context
How big was it, and why here?
Energy released
60 tons of TNT
That is about 1/251 of the Hiroshima bomb. A magnitude 5.0 releases about 8 times more energy.
Tectonic setting
287 km
from the nearest mapped plate boundary, between the Altiplano and South American plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: intermediate
77 km
Intermediate-depth earthquakes usually break inside a plate that is sinking into the mantle. Shaking spreads over a wide area but is gentler at the epicenter than a shallow quake of the same size.
Did You Feel It?
Where it was felt
No “Did You Feel It?” reports have been published for this event yet. If you felt it, you can add your report on the USGS website.
I felt it — report to USGS ↗USGS PAGER estimate
Who was exposed to shaking
USGS publishes PAGER impact estimates for significant earthquakes, usually within an hour. No PAGER estimate is available for this event.
After the main event
Aftershocks within 50 km
USGS lists 3 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M4.4 on May 4, 2007. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 340 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.2121 km SSE of San Pedro de Atacama, ChileDecember 9, 1950 · 154 km W of this epicenter
- 7.275 km N of San Antonio de los Cobres, ArgentinaMay 12, 2000 · 61 km N of this epicenter
- 7.116 km NW of Villazón, BoliviaJanuary 23, 1997 · 243 km N of this epicenter
- 7.087 km W of Abra Pampa, ArgentinaMay 24, 1993 · 159 km N of this epicenter
- 7.052 km W of Abra Pampa, ArgentinaApril 1, 1987 · 149 km N of this epicenter
- 6.930 km SSE of Santa Clara, ArgentinaAugust 25, 1948 · 197 km E of this epicenter
- 6.999 km WNW of San Antonio de los Cobres, ArgentinaFebruary 21, 1971 · 86 km NW of this epicenter
- 6.840 km SE of San Pedro de Atacama, ChileAugust 3, 1962 · 186 km NW of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 10 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 32 recorded deaths. The most severe:
- 1930M6.1
La Poma
24 Dec 1930 · 149 km away · intensity VIII
31 deathsSevere damage ($5–24M)
- 1950M8.0
Chile-Argentina
9 Dec 1950 · 130 km away · intensity VII
1 death
- 1844M6.5
Salta, Jujuy, Tucuman
19 Oct 1844 · 108 km away · intensity VII
Severe damage ($5–24M)
- 1948M6.9
Salta
25 Aug 1948 · 197 km away · intensity IX
Moderate damage ($1–5M)
- 1959M6.6
Salta
12 May 1959 · 190 km away · intensity VIII
Moderate damage ($1–5M)
- 1863
Jujuy
14 Jan 1863 · 153 km away · intensity VIII
Moderate damage ($1–5M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.